We critically review literature that examines variation in temperature‐dependent sex determination (TSD) within species. Although variation in sex ratio among clutches of eggs from different females is common in reptiles with TSD, the underlying mechanism that causes this variation is not clear. Authors have made claims about genetic variation in TSD and maternal effects on TSD. The latter type of study usually focuses on maternally derived steroids in egg yolk. Here, we outline the types of experiments and data required to unequivocally demonstrate that variation in sex ratio among clutches (1) has a genetic basis, (2) is caused by maternally derived steroids, or (3) is influenced by both factors. To date, few studies have met these requirements.
- Award ID(s):
- 1656048
- NSF-PAR ID:
- 10250975
- Editor(s):
- Shaffer, Bradley
- Date Published:
- Journal Name:
- Journal of Heredity
- Volume:
- 112
- Issue:
- 2
- ISSN:
- 0022-1503
- Page Range / eLocation ID:
- 155 to 164
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Global climate is warming rapidly, threatening vertebrates with temperature-dependent sex determination (TSD) by disrupting sex ratios and other traits. Less understood are the effects of increased thermal fluctuations predicted to accompany climate change. Greater fluctuations could accelerate feminization of species that produce females under warmer conditions (further endangering TSD animals), or counter it (reducing extinction risk). Here we use novel experiments exposing eggs of Painted Turtles (
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Abstract In contrast to genotypic sex determination (GSD), temperature-dependent sex determination (TSD) in amniotic vertebrates eludes intuitive connections to Fisherian sex-ratio theory. Attempts to draw such connections have driven over 50 years of research on the evolution of sex-determining mechanisms (SDM), perhaps most prominently among species in the order Testudines. Despite regular advancements in our understanding of this topic, no efforts have been published compiling the entirety of data on the relationships between incubation temperature and offspring sex in any taxonomic group. Here, we present the Reptilian Offspring Sex and Incubation Environment (ROSIE) database, a comprehensive set of over 7,000 individual measurements of offspring sex ratios in the order Testudines as well as SDM classifications for 149 species. As the name suggests, we plan to expand the taxonomic coverage of ROSIE to include all non-avian reptiles and will regularly release updates to maintain its comprehensive nature. This resource will enable crucial future research probing the ecology and evolution of SDM, including the presumed sensitivity of TSD to rapid environmental change.
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/jhered/esab006
